title: Comparison between a novel nickel-titanium alloy and 508 nitinol on the cyclic fatigue life of ProFile 25/.04 rotary instruments.
abstract: ProFile 25/.04 instruments manufactured from three variants of Nitinol (1A, 1B & 2AS) were compared with stock production ProFile 25/.04 instruments and fatigue tested to failure. Cyclic fatigue testing was performed by rotating instruments at 300 RPM in a simulated steel root canal with 5 mm radius and 90 degrees curve until instrument separation. Time to failure was recorded. Torsion testing was undertaken by clamping 3 mm of each instrument tip between brass plates and rotating it at 2 RPM until failure. Data were recorded for torque and angle at fracture. Statistical differences were found with nickel-titanium variant 1B (M-Wire NiTi) nearly 400% more resistant to cyclic fatigue than stock ProFile 25/.04 (P < .001). Torsion testing found differences between all 508 Nitinol groups and M-Wire NiTi (P < .001). ProFile 25/.04 files manufactured from M-Wire NiTi have significantly greater resistance to cyclic fatigue while maintaining comparable torsional properties.
authors.affiliation: Department of Endodontics, Nova Southeastern University College of Dental Medicine, Health Professions Division, Fort Lauderdale, FL.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Johnson
authors.affiliation: Department of Endodontics, Nova Southeastern University College of Dental Medicine, Health Professions Division, Fort Lauderdale, FL. Electronic address: lloyda@nova.edu.
authors.forename: Adam
authors.initials: A
authors.lastname: Lloyd
authors.affiliation: Department of Endodontics, Nova Southeastern University College of Dental Medicine, Health Professions Division, Fort Lauderdale, FL.
authors.forename: Sergio
authors.initials: S
authors.lastname: Kuttler
authors.affiliation: Department of Endodontics, Nova Southeastern University College of Dental Medicine, Health Professions Division, Fort Lauderdale, FL.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Namerow
mesh_terms: D000497:Alloys / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry*; D003762:Dental Instruments; D003799:Dental Stress Analysis; D004868:Equipment Failure; D008422:Materials Testing; D009532:Nickel / Q000737:chemistry; D018915:Root Canal Preparation / Q000295:instrumentation*; D014025:Titanium / Q000737:chemistry; D019415:Torque; D054159:Torsion, Mechanical
chemical_list: D000497:Alloys; D003722:Dental Alloys; C040654:titanium nickelide; C013616:nitinol; D009532:Nickel; D014025:Titanium